Mechanism for the automatic regulation of the braking force of compressed-air brakes



- H. MULLER MECHANISM FOR THE AUTOMATIC REGULATION OF THE BRAKING FORCE 0F COMPRESSED AIR BRAKES Filed March 21,. 1924 Patented May 12, 19255.,

1,537,5 Fr es..-

EERMA'NN' manna, or ISIEGEN, GERMANY.

MECHANISM FOR THE AUTOMATIC REGULATION OF THEBBAKING FORCE OF COMPRESSED-AIR BRAKES.

Application filed ma 21, 1924. Serial at. 700,911.

braking force being eifected independently of the usual regulating by hand by the attendants as this latter regulating is frequently effected too late to prevent the considerable damage. which results from' the slipping of the braked wheels on the rails.

This damage consists in that the treads of the wheels are ground out of true whereby the steady running of the cars is impeded,

- the duration of the cars and of the earth works being considerably reduced.

The automatically acting regulating mechanisms of known type are mounted on the brake axle of the car and they are by the changing state of movement of the axle in such a manner that at the transition from revolution to the state of rest of the axle during the braking the air outlet valve of the brake cylinder is opened so that the brake pressure is reduced whereby the brake shoes are released whereupon the action on the valve ceases. The regulating devices of known type are either centrifugal governors which, according to the state of movement of the brake axle, produce a relative movement between the coupling elements and controls, with the aid of transmission means like levers, traction ropes or the like, the air outlet valve, or the kinetic energy of a rotating ring which, with regard to the brake axle at the stand still of the same during the braking, executes an angular rotation, is utilized to control the air outlet valve of the. brake cylinder with the aid ofthe above-mentioned transmission means.

The mechanisms of known type possess the serious inconvenience that they act directly upon an air outlet valve on the brake cylinder so thatowing to the long distance between the brake cylinder and the brake axles of the carlong mechanical transmission means are required, for which very of which influenced often there is not suflicient space and which, owing to the great length, become so complicated and difficult to operate that the de sired effect fails frequently.

This invention avoids these inconveniences by making the regulating device on brake axle act directly upon a slide valve arranged in closest. proximity to it, said slide valve communicatingwith the pressure space of the brake cylinder by a pipe conduit or the like which can be easily displaced, the brake pressure in this space being regulated through the intermediary of this pipe conduit. The regulating device itself utilizes for the operation of the slide valve also a rotating ring of known type rotatable around a bearing rigidly connected with the brake axle, but it differs from the regulating mechanisms of known type essentially by the means for transmitting to the valve slide the movement of the rotating ring designed to control the slide valve. It may be especially pointed out that the slide is perfectlyflrelieved and requires consequently only very feeble driving power.

An embodiment of the invention is shown by way of example on the accompanying drawing in which:

Fig. 1 is a front elevation,

1 1EFig. 2 aside elevation viewed from the e t, i

Fig. 3 a plan view, and

Fig. 4 a side elevation viewed from the right.

On the axle a of the wheels to be braked, which willherei nafter be called the brake axle, a. long sleeve 1), similar to a hub, is keyed which terminates at one end in a flange c. A rotating ring d is loosely mounted on sleeve b at a short distance from the fiangec. This rotating ring d has four lugs a designed to receive each a bolt 1 having on its part above the lug a spring g This arrangement serves to couple the rotat ing ring (1 with the sleeve 7) however in such a manner that, under conditions which the will be hereinafter explained, it may execute a relative movement with regard to the axle a. The rotating ring (1 has a neck bearing and pressed the one against the the action of springs j mounted are separated from one another ing upon the sliding ring may be regulated.

All the ring-shaped or sleeve-shaped elements mounted on the axle are made of two parts so that they can be easily mounted on the axle. An arm Z of the sliding ring engages with aslit of an eye m of a valve rod which belongs to a relieved piston valve .2 with packing rings 19,1)" and [9 In the valve casing radial ports 9 and a" are arranged. The ports 1' are connected with the pressure. spaces of the brake cylinder 25 by a, tubularconduit a, and the ports 9 communicate with the atmosphere. Owing to the packing rings 2, p, p the ports of the casing may' either, at a determined zero position (Fig. 2), be connected with one another or shut off as soonas the piston valve arrives in the position I or II. The valve casing is fixed on the frame of the car. The eye ml of the push rod u has a longitudinal slit in order to ensure that the movements of the car frame with regard to the corresponding wheelor brake axle does not influence the connection between the push rod and'the' sliding ring. When the axle a revolves in d continues to rotate by the action of its kinetic energy and puts under tension one,

of the springs g on the connecting bolts f. .When the rotation of the rotating ring ceases this rotating ring is returned to the zero position (Fig. 2) by the action of the expanding spring. The sliding ring 5 will participate in this return movement and ad' just the piston valves to the zero position whereby air is made to flow out of the brake cylinder until the brake shoes are released and the axle a begins to revolve again, the piston valve 2 being returned by the sliding ring immediately into two positions I or II.

I claim 1. A mechanism for the automatical regulation of the braking force of compressed air brakes for railway cars designed toprevent the slipping of the braked wheels on the rails, comprising in combination with the brake cylinder and with the brake axle, a relieved piston valve, a casing of said piston valve fixed on the frame of the car, a tubular conduit connecting said valve .casing with the pressure space of the brake cylinder, a rotating ring on the brake axle,

a sliding ring loosely mounted on 'saidrotatingringfand means for connecting'said slld- I .vent the slipping of the brake i piston valve into a position in which 1; e

ing ring with said relieved piston valve so that said piston valve regulates the air pres sure in the brake cylinder owing to the displacements in the casing within determined limits.

the brake cylinder and with the brake axle,

a relieved piston valve, a casing of said piscommunicating with the atmosphere fixed :on the frame of the'car, a tubular conduit connecting said second mentioned port of ton valve-having two ports one of which the valve casing with the pressure space of I the brake cylinder, a rotating ring' onthe brake axle, spring controlled means for movably fixing said rotating ring on the brake axle, a sliding ring loosely mounted on said rotating ring so that at the starting of the car in any direction said sliding ring is drawn along by said rotating ring for a part revolution, and means for connecting said sliding ringwith said relieved piston valve so that said sliding ring at its part revolution brings said piston valve into'a. position in'which the port of the casing communicatin with the pressure space 'of the brake cy inder is closed which ort, when the brake axle stops'suddenl uring the brak ing, will be automatica y opened b said sliding ring which is revolved back y the action of the spring of the rotating'ring r'elleased by the sudden stop of the brake ax e.

' 3. A mechanism for the automatical regulation of the braking force of compressed air brakes for railway cars designed to prethe rails, comprising in combination with p the brake cylinder and with the brake axle,

wheels on I a relieved iston valve, a casing of said piston valve aving two ports one of which communicating with the atmosphere gfixed on the frame of the car, a tubular conduit connecting said second mentioned port of the valve casingwith the pressure space of the brake cylinder, a rotating ring on the brake axle, spring controlled means for movably .fixing said rotating ring on the loosel mounted brake axle, a sliding ring at at t e starting on said rotating ring so t of the carin'any direction said sliding ringis drawn along by said rotating ring for a part revolution, the movement of the sliding ring being determined by the stroke of the,-

piston valve which is stopped in either direction by the'end. walls 0 the casing, and means for connecting said sliding ring with said relieved piston valve so that said sliding ring at its part revolution bri said port of the casing communicating with the pressure space of the brake cylinder is closed which ort, when the brake axle stops suddenly uring the braking, will be automatically opened by said sliding ring which is revolved back by the action of the spring of the rotating ring released by the sudden stop of the brake axle.

4. A. mechanism for the automatical -regulating of the braking force of compressed air brakes for railway cars desi ed to prevent'the slipping of the -braked wheels on the rails, comprlsing in combination with arms of said rotating ring, a radial arm of said bearing of the brake axle, bolts one at either side traversm said radial arms of the rotating ring an of the bearing, com- 'pressible springs inserted between one of said radial arms of the rotating ring, a sliding ring loosely mounted on said rotating ring so that at the starting of the car in any direction said sliding ring is drawn along by said rotating ring-for a part revolution,

and means for connecting said sliding ring I with said relieved piston valve so that said sliding ring at 'its -partrevolution brings said piston valve into-"a position in which the port of the casing communicating with the pressure-space .of the brake cylinder is closed which port, when the brake axle stops; suddenly during the brakin ,will be automatically o ened by 'said sli mg ring'which is revolved ack by the action of the spring of the rotating ring released by the sudden ship of the brake axle. v 4

testimony whereof I aflix my signature in presence of two Witnesses. p

' HERMANN MULLER.

' Witnesses:

WILHELM Rum, CARI. KHOLL. 

